1. Field of the Invention
The invention relates to production and precision patterning of work pieces, including manufacture of photomask for photolithography and direct writing on other substrates, such as semiconductor substrates. In particular, it relates to applying corrections to pattern data, such as corrections for distortions in the field of an SLM exposure stamp. It may be used to produce a device on a substrate. Alternatively, the present invention may be practiced as a device practicing disclosed methods or as an article of manufacture, particularly a memory, either volatile or non-volatile memory, including a program adapted to carry out the disclosed methods. Additional aspects of the invention are further described in the accompanying description, figures and claims.
2. Related Art
A variety of distortions related to maskmaking are described in the WO application referred to above. These distortions typically relate to physical properties of the substrates on which the patterns are printed, i.e. the mask blanks and the wafers or panels, the position on the substrates, the exposing equipment (which can use electromagnetic radiation or particle beams) including the exposing sequence and environment, and the pattern itself. Other potential sources of distortion are noted.
Passing reference is made in the WO application to applying distortion corrections when writing directly to a workpiece using an SLM, on pages 31, 33, and 35-36. These references generally relate to correcting distortions using an SLM and do not describe distortions particular to an SLM.
Experience using an SLM has revealed that some additional types of distortion, not mentioning the WO application, arise when an SLM is used. Nominal stamp location, rotation and magnification errors are among the additional types of distortion that deserve attention, as is spatial distortion across the field of an SLM.
Accordingly, an opportunity arises to address types of distortion particular to the use of SLMs and to apply technologies particularly available in SLMs to a wide range of distortions.